Automatic railway crossing gate



May 14, 1935. A. E. M CLAREN 2,001,147

AUTOMATIC RAILWAY CROSSING GATE I Filed Sept. 14, 1932 3 Sheets-Sheet 1f l lllll l l lmll Ilium 1mm?- gin/Denim;

May 14, 1935. A. E. McCLAREN 2,001,147

AUTOMATIC RAILWAY dRQSSING' GATE Filed sefn. 14, 1952 s Sheets-Sheet 2 E20/ x\\\\\\\\\7/////////////////A\\\\\\ gwuentoa y 1935.. A. E. MCCLAREN2,001,147

AUTOMATIC RAILWAY CROSSING GATE Filed Sept. 14, 1932 5 Sheets-Sheet 3gmmtoz I A. E. MCCZAEE/Y Patented May 14, 1935 oN-ir s res soronm'rioRAILWAY GROSSING GATE runes E. McClaren, Joplin; Mo. ApplicationSeptember 14, 1932, sen-amateuris- 10 class. (01. 246-128) Thisinvention relates to automatic railway crossing gates, and-moreparticularly to a gate operat'ihgmechanism controlled by trainsapproaching a grade crossing for operating the gates to lower them uponthe approach of the train and to'raise them after the train has passed.V

An important object of the invention is to provide a novel form ofcontrol mechanism for er"- f'e'cting automatic'lowering of the gates ata railroad grade crossing uponthe approach of a train.

A further object is to provide an apparatus of the character referred towherein thetime of the lowering of the gates is automatically depend- Ient upon-the speed of the approaching train whereby the gates will reachlowered position at approximately the sametime the train reaches thegrade crossing substantially regardless of the speedofthe train.

A: further object 'is to provide electricallycontrolle d' powermechanism for operating the gates; and wherein a control block isprovided adjacent the grade crossing whereby control of the mechanism iseffected by the entrance of a train intothe block rrom. eitherdirection.

A further object isto'provicle an apparatus of the character referred towhich does not disturb the use of the control block for switching orother purposes, means being provided for so employing the block withoutneedlessly raising and lowering the gates.

A further object is to provide novel power means for moving the gatesbetween vertical and horizontal positions, such means'being in the formof setsoflaxially aligned solenoids adapted to be progressively broughtinto operation through suitable automatic means for moving the gatesbetween the two positions.

A further object is to provide novel circuits adapted to be energizedupon the entrance of a train; into the control block and having suitabletime controlled means associated therewith whereby the highway gateswill be lowered relatively promptly if the train is moving at such arateas to pass a predetermined distance into'the block within a giventime after entering it, the time controlled mechanismbeing such as toprevent operation of the gates by a relatively slow lmoivingj trainexcept through additional means arranged to be controlleolby a train asit approacheszthe highway.

Other objects and advantages of'th'e invention will become apparentduring the course of. the a follbwing description; 1

In the: drawings I have shown one embodiment of theinventiont- In thisshowing,

Figure 1' is a diagrammatic View showing the electrical: system embodiedin the invention,

Figure 2 is a side elevation of oneofthe crossing gates-, a portion ofthe gate being broken away,- l

Figure 3 is a section" taken substantially on line 3-3: of Figure 2',parts being shown in elevation,

Figure 4a-is a section taken substantially on line t -t of Figure 3,parts being omitted,

Figure 5 is a detail sectional view on line 55 of Figure 3,

Figure 6 is a detail sectional view time controlled solenoid andassociated elements, and

Figure 7 is a diagrammatic sectional View illus-r trating theelectrical: means and wiring connections therefor" employed for raisingand lowerin'g'the gates.

Referring to: Figure 1 the numeral Hi desig-' nates the rails of: arailroad over which passes a highway diagrammatically illustrated as atll. One" rail is: provided with a section t2 insulated as at. E3; fromthe adjacent portions of the corresponding'rail', and'thesec'tion i2 isof substantial length. In practice; it has been found advisabletoextendv the rail for a distance of substantially one thousand feet.to" each side of the center of "the highway, thus making therail sectionl2 approximately two thousandfeet long and electrically c'onnected fromend to end. l i The other rail is provided witha pair of sectionsWhaving their adjacent ends arranged substantially centrally of thehighway and insulated from each other as at [5; The remote ends of thesections M" are insulated: from the adjacent cor responding rails as atHis. Each of therail sections M is preferably approximately one thousandfeet in length and accordingly the remote ends of the sections Hi" lieopposite the ends of the section I 22. The railsections l2 and Itaccordingly constitute a control block to be referred to in detaillater. I

Referring to Figure 1' the numeral H designates a source of currenthaving one terminal grounded asat Is and the opposite terminal'connectedto the rail section H? by a wire I9. The passage of the train over therails i2 and M is adapted to close .certain circuits to be referred toby electrically I suitable point. and: have coils: grounded at. one

through the 1 end respectively as at 22 and 23. The other terminal ofthe coil 28 is connected by a wire 24 to a contact 26. The otherterminal of the coil 2| is connected to one end of a Wire 28 to bereferred to in detail later, and a wire 29 is connected from the wire 28to a contact 38 similar to the contact 26. The contacts 25 and 38 arecarried by the ends of a lever 3| pivotally supported intermediate itsends as at 32. The lever 3| may be formed of insulating material, or thecontacts 26 and 38 may be insulated therefrom.

The wire 27 has one end connected to one of the rail sections I4 and theother end of the wire is connected to a contact 33, carried by a bar 34preferably formed of insulating material. Springs 35 normally urge thebar 34 upwardly to hold the contact 33 in engagement with a contact 38acting as a stop to limit the upward movement of the bar 34.

The bar 34 is provided at opposite ends with contacts 31 and 38engageable under certain conditions with the contacts 25 and 38respectively. The contact 3'! is connected to the wire 21 by a lead wire39, while the contact 38 is connected by a wire 48 to a junction box 4|.The bar 34 is provided with armatures 42' for the respective magnets 28and 2|.

A second assembly of magnets similar to the magnets 28 and 2| and theirassociated elements also is employed. Referring to Figure l, thenumerals 42 and 43 designate a pair of magnets having their respectivecoils grounded at one end as at 44 and 45. A lever 46 is pivotallysupported intermediate its ends as at 41 to one side of the coils 42 and43 and carries contacts 48 and 49 at its ends. The lever 48 is similarto the lever 3| previously described and may be formed of insulatingmaterial.

The other terminal of the magnet 42 is connected by a wire 58 to thecontact 38, and the wire 58 has a branch 5| leading to the contact 48.The second terminal of the magnet 43 is connected by a wire 52 to thecontact 49. The contacts 48 and 49 are respectively engageable withcontacts 53 and 54 carried by the ends of a bar 55 formed of insulatingmaterial. This bar carries armatures 58 and 5?. for the respectivemagnets 42 and 43, and a contact 58 is carried by the bar 55 centrallythereof for engagement with a contact 59. Springs 58 urge the bar 55upwardly under normal conditions to hold the contact 58 in engagementwith the contact 59, and the latter contact acts as a stop to limit theupward movement of the bar 55.

The contact 53 of the bar 55 is connected by a wire 6| to the junctionbox 4| The wire 28, previously described, leads to the stop contact 59.The contact 54 of the arm 55 is connected to one end of a wire 82leading to the right hand rail section I4. A branch wire 83 is connectedbetween the wire 62 and the contact 58.

A wire 64 has one end connected to the junction box 4|. The other endportion of the wire 64 forms a supply wire for a plurality of contactsarranged between the rails. As shown, contacts 65 and 66 are arrangedadjacent the remote ends of the respective rail sections I4, and inpractice, the contacts 65 and 55 are arranged approximately one hundredfeet from the ends of the control block. The contacts referred toobviously are supplied with current from the wire 84, and such wire alsois connected to inner contacts 61 and 88 arranged fairly close to theinner ends of the rail sections I4.

The contacts 65 and 66 are engageable by depressible contactors 39 andI8 respectively, and these contactors are operable by the wheels of atrain passing thereover. Wires II and I2 are connected to the respectivecontactors 69 and I8 and are joined at the point I3 to supply currentunder certain conditions to electrical devices to be referred to. Thecontacts 57 and 88 are engageable with depressible contactors I4 and I5respectively, operable by the wheels of a train passing thereover. Thelast named pair of contactors have a connecting wire I6 and a commonwire 11 leads from the wire I8 for a purpose to be described.

A control magnet indicated by the numeral I8 has one terminal of itscoil grounded as at I9. The other terminal of the coil of magnet 18 isprovided with two take-off wires one of which indicated by the numeral88, leads to a stationary post 8|. This post constitutes a contactengageable with a second post 82 pivotally connected at its lower end toa base 83. The junction point 13 is connected to the base 83 by a wire84. The second wire 85 from the last mentioned terminal of the magnet 88leads to a contact 86. The magnet !8 is provided with an armature 87carried by a bar 88 formed of conducting material. The lower end of thebar is pivotally supported by a base 89 connected by a wire 98 to thejunction box 4|. The bar 88 is provided with a spring 9! urging it awayfrom the magnet I8 and its movement is limited by a stop contact 92connected to one end of a wire 93. The bar 88 is provided with a contact94 engageable with the contact 85, and is further provided at its upperend with a contact 95 for a purpose to be described.

A control solenoid 98 is arranged adjacent the r magnet 58 as shown inFigures I and 6, and one end of the coil of the solenoid 95 is groundedas at 91. The other terminal of the solenoid coil is connected to thewire 93 previously described. The solenoid 96 is provided with a tubulararmature 98, closed at its outer end as shown in Figure 6. At its outerend the armature 98 carries a contact 99 engageable with the contact 95.The armature 98 is provided with a tubular extension I89 projectingcompletely through the solenoid 96 and connected to one end of a bellowsIEII arranged in axial alignment with the solenoid 9B. The opposite endof the bellows is supported by a post I 82.

A spring I83 is arranged in the bellows to urge the tubular member I88and armature 98 toward the left as viewed in Figure 6, and the flangedend of the tubular member I88 engages the end of the solenoid to limitthe movement of the parts referred to. A check valve I84 is connected tothe bellows I8I and permits restricted escape of air therefrom. Thecheck valve is operative to substantially prevent the movement of airinto the bellows when the latter expands. The rate of discharge of airthrough the valve I84 is controlled by an adjustable handle I85 whichdetermines the opening movement of the check valve. The escape of airfrom the bellows also takes place through a valve I88 cooperating with aseat I81 leading into the interior of the armature 98. Any suitablemeans may be employed for guiding the valve I86, and in the presentinstance the valve has been shown as being provided with a stem I88slidable through the armature 98. A spring I89 normally urges the valveI86 toward open position as will be apparent. A valve control plate H8is carried by the solenoid 96 and projects therefrom. This plate has aninclined face III engageable with a roller I I2 carried by the upper endof the valve stem I88, and it willbe apparent c llly the positions shownin Figures 1 and 6 with the contacts 95 and 99 out of engagement witheach other, and these contacts are engageable under conditions to bereferred to for connecting the contact 95 to the wire 11. For thispurpose, the contact 99 1s provided with a wire I I3 leading to the wire11, and accordingly the contact 95 will he electrically connected to thewire 11 when the contacts 95 and 98 are brought into engagement wi h;each other. The engagement between these contacts is dependent uponenergization of the magnet Iii to attract its armature and energizationof; the magnet 18 is dependent upon the closing of its circuit acrossthe posts ill and 82. Under some conditions of operation energization ofthe magnet .18 is prevented, and for this purpose, the armature 98 isprovided at its free end with a depending lug H4 engageable with theprojecting upper end of the post 82 when the armature 53 is fullyretracted. As previously stated, the posts 8| and 82 may electricallyengage each other or may be provided with conpost 82. i

The wire 11 shown in Figure 1 leads to a junction box H8 having a pairof contacts H9 and The contact H9 is connected to the end of the wire11; while the contact I20 is connected to :uone end of a wire I21leading from the bar 88 or its base 89. Parallel wires I22 and I23 areprovided for the purpose of shunting the circuit across the contacts 9'and I20 by either of a plurality of devices to be described.

The numeral I24 designates a magnet having one terminal of its coilgrounded as at I 25; The other terminal of the coil is connected to oneend of a wire I26, and this wire leads to a wire'l21 extending betweenthe contact I I9 and a contact 28. Another contact I29 is arrangedopposite the contact I23 and these two contacts are carried by the endsof a lever I36; preferably formed of insulating material and pivotallysupported Intermediate its ends. A bar IZl carries the armature t32 ofthe magnet lztvand is urged down- A center contact I31 is carried by thebar l3 I and the springs I33 normally retain this contact in engagementwith a contact I38. A wire l39 leads from the contact I38 toa junctionbox 155 and is connected toa contact MI therein. A wire I42 leads fromthe contact MI for a purpose to be described. A wire I43 also leads fromthe contact I23 to the junction box M and is connected to I the secondcontact I44 therein. An outlet wire M5. leads from the contact l l-l'for a purpose tobe described. Current for the circuits including thewires just described may be supplied from the source I1 previouslydescribed, but is preferably supplied froma source I46 of highervoltage. One terminal of this source is provided with a wire I411leading to the contact. [35, while the other terminal of the source isprovided'with a wire 1 I 48 for a purpose to be described. A wire I38connects wire I41 to contact I31.

Current from thesource I45 is utilized in a manner to be described tolower gates at the grade crossing, and the closing of circuits for thispurpose is dependent upon the closing of a circuit across the contacts II9 and I20. This is accomplished in a manner to be. described throughthe various mechanisms previously referred to, and severalauxiliarydevices may be separately or severally employed for closing thecircuit across the contacts H9 and I26 if desired under certainconditions. 7 be noted that the wires I22 and I23 are connectedrespectively to the contacts II8and H9 and the latter accordingly willbe bridged whenever electrical contact is established across the wiresI22 and IE3. For example, an ordinary switch M9, such as a knife switch,may be en.- gageable with a contact I50 and the switch and contact areconnected respectively to the wires- Alternatively, a push button l5II22 and I23. may be provided for the same purpose, as may a depressorswitch E52; If desired a microphone I5? may be provided to bridgeacrossthe wires I22 and I23, and this microphone may be adjusted so asto be sensitive to the vibrations caused by the blowing of alocomotivewhistle.

The crossing gates have been illustrated diagrammatically in Figures 1and 'land structurally in Figures 2, 3, l, 5 and 7. Referring to Figures2 and 3, the numerall54 designates a suitable casing in which isarranged the mechanism for operating the gates. The: casing I54rotatably supports a shaft I55 to one end of which is connected anysuitable form ofgate I56 preferably provided with a counterweight I51. Asleeve I58 rotatably surrounds theshaft I55 within the casing and isprovided with a wheel lee having a groove I65. in itspen'phery toreceive 'a cable IfiI. The ends of the cable are connected respectivelyto armatures I52 and I53 (see Figure 7) and the armaturcs operaterespectively to rotate the wheel I59 and thus operate the gate 556. Asshownin Figure '7, the armature I62 is movable through the cores ofaxially aligned solenoids I 64., while the armature I63 is similarlymovable through the cores of a plurality of axially aligned solenoidsI55.

The solenoids I64 are successively energized from the uppermost to thelowermost solenoidtolower the gate I56, while the solenoids I65 aresuecessively energized in asimilar manner after the gate has beenlowered for returning it to the uppermost position. The control circuitsfor the two series of solenoids I54 and I65 will be re-- ferred tolater.

Referring to Figures 3 and 4, the numeral I66 designates a leverconnected centrally thereof to the sleeve I58. The ends of this leverare turned outwardly to form ears 861. in which arev arranged eye boltsI58. Springs 69 of the ten sion type are connected at their outer endsto the eyes of the bolts I68 and these springs have their inner endsconnected to a pin I extending through the shaft I55.

Referring to Figure 1, it will A bracket IN is arranged within thecasing I 54 and is provided at its upper end with a series of arcuatelyarranged contacts I12, suitably insulated from each other and engageablewith'a contact I13 carried by the lever I156. The arrangement ofthecontacts I12 is shown diagrammatically in Figure 7. Starting from oneend, such as the left hand end shown in Figure 7,

the contacts I12 are connected to the. successive,

uppermost solenoid. The

solenoids I64, starting from the uppermost solenoid, by wires H4. Thewires I14, in turn, are successively connected to the solenoids I65,commencing with the lowermost solenoids, by wires I'I5. Accordingly itwill be apparent that the contact I12 at the extreme left side in Figure7 is connected to the uppermost solenoid I64 and to the lowermostsolenoid I65, while the extreme right hand contact I12 is connected tothe lowermost solenoid I64 and to the uppermost solennoid I65. Thecontact I'I3 has been diagrammatically represented in Figure 7 as an armmovable with the gate I56, and as the gate swings downwardly in thedirection of the arrow, it

will be apparent that the contact HS successively engages the contactsI'i2 until the contact I12 at the extreme right is reached, at whichpoint the gate will be in a horizontal position. During such operation,the successive solenoids I64 starting from the uppermost solenoid, willbe energized, and during the return movement of the gate to verticalposition the contact I73 will move toward the left and will successivelyenergize the solenoids I65, starting from the circuits for accomplishingthese two results will be referred to in detail later.

While only one of the gates I56 has been described, it will be apparentthat gates are provided at each side of the grade crossing, and

accordingly two gates have been illustrated in Figure 1, and such gateswill be electrically connected to operate simultaneously. Referring toFigure 1, it will be noted that the wire I48 from the source I46 isconnected to the shaft of one of the gates I56, and in practice, thewire will be merely grounded on the casing I54. A branch wire I'I'Ileads from the wire I 48 to the other gate unit in a similar manner.

Current is supplied to the solenoids I64 and I65 in the mannerpreviously described, and the upper gate unit shown in Figure 1 isprovided with return wires I18 and I I9 connected to the solenoids ofthe respective series 194 and I65. The wires I18 are connected to thewire I45 and thus lead to the contact I44. The wires H9 are connected tothe wire I 42, and thus lead to the contact I 49.

The solenoids of the series I 64 and E65 of the lower gate unit shown inFigure 1 also are provided with return wires I89 and I8I respectively,and the wires I80 are connected by a wire 82 to the wire I45. The returnwires I8 I are connected to a common wire E83 which, in turn, isconnected to a wire I84 leading to the wire I 52. Thus it will beapparent that the corresponding series of solenoids of the two gateunits are connected in parallel.

The shaft I55 of each gate unit is provided with a switch arm I85 (seeFigures 1 and 3) and this switch arm is operable over a segmentalcontact I86. When the gate of each unit is in vertical position, theswitch arm I85 is out of contact with its associated contact I86, butengages such contact as soon as the gate starts downwardly and remainsin engagement therewith until the gate returns to normal verticalposition. Each contact I86 is grounded as at I81.

Each gate is preferably provided with a signal light I88 connected tothe associated switch arm I85 by a wire I89. A wire I99 connects eachlight I88 to one post of a bell I9I or other audible signal. The otherposts of the audible signals are connected to one side of the source ITby wires I92 and I93.

Means are preferably provided for preventing too rapid movement of thegates I56 as they approach their limits of movement. Such means need notbe employed, but preferably is used to eliminate any possible damage tothe parts. Referring to Figure the numeral I94 designates a pair of dashpot cylinders having pistons I95 therein provided with restricted portsI96 extending therethrough. These pistons are provided with piston rodsI97 extending upwardly above the dash pots and having their upper endsslotted as at I98. The shaft I55 of each gate unit is provided with alever I99 secured thereto and provided at its ends with pins 209operating in the slots I98. Each dash pot is provided at its lower endwith a depending ear 20 I through which passes a pivot pin 202 topivotally connect the dash pots to the casing I54.

The operation of the apparatus is as follows:

Assuming that a train approaches the control block from the left side asviewed in Figure 1, the entrance of the locomotive into the blockelectricarly connects the rail I2 and the adjacent rail section I4through the wheels and axles of the locomotive. Under such conditions,current will flow from the battery H through wire I 9 and rail 52,through the locomotive to rail I4, through wire 2'! and. contacts 33 and36, through wire 50 to magnet 42, and thence back to the source I1through grounds 44 and I 8. Thus the magnet 42 will be energized toattract its armature 56, and the entire bar 55 will be moved downwardlyagainst the tension of the light springs 60 to bring the contacts 53 and54 into engagement with the respective contacts 48 and 49 of the lever46. In this connection it will be noted that the lever 45 is pivotedintermediate its ends and accordingly is adapted to swing about itspivot to insure proper engagement between the contacts of the lever andthe contacts 53 and 54.

The circuit through the magnet 42 includes the wire 59, as previouslystated, and this wire is connected to the branch wire 5| leading to thecontact 48. This contact is now in engagement with the contact 53 due tothe energization of the magnet 42, and the contact 53 is connected tothe junction box 4| which is merely a single common binding post for thevarious wires leading thereto.

Accordingly current will flow to the junction box 4|, and the point 4|is connected through wire 64 to the several track contacts 65, 66, 6'!and 68, and depression of any of the switches associated with the trackcontacts, under such conditions, will close circuits to be referred tolater.

The junction point 4I likewise is connected through wire 99 to the base89 and thus to the bar 96. Accordingly current will flow through wire96, base 89, bar 88, stop contact 92 and wire 99, and thence throughsolenoid 96 and back to the source through grounds 9'! and I8.Accordingly it will be apparent that the entrance of a train into theblock from the left side as viewed in Figure 1 causes immediateenergization of the presses the bellows, and the check valve I94 opensto permit the escape of air therefrom.

'When the armature 98 is in its outermost position as shown in Figure 6,the inclined plate I I I, operating against the roller II2, holds thevalve I06 substantially in closed position thus minimizing the escape ofair from the armature 98, tubular member I90 and bellows IBI, as thearmature moves inwardly. Thus the solenoid 96 is preventedfrom rapidlyoperating its armature; and the latter moves inwardly very slowly at thebeginning of its movement, but such movement progressively increasesduring inward movement of the armature since the roller I I 2 travelsupwardly along the inclined plate I I I, thus permitting the valve I06to progressively open.

The operation of the circuits which are controlled by thev armature 98and contact 99 will depend upon the speed with which the train entersand travels through the control block. For example, it is preferred thatthe solenoid 96 should cause movement of its armature to comcontactors99 when the'contacts H and IIS are separated will prevent energizationof the magnet 18. In other words, if it requires the front wheels of theapproaching locomotive more than approximately four seconds to travelfrom the entrance of the block to the contactors 69', the magnet I8 willnot be energized, and certain circuits dependent upon this magnet willnot be closed. f

Assuming however that the train travels into the entrance of the blockat aspeed which will cause the front wheels of the locomotive to reachthe contactor 69 in less than approximately four seconds, a whollydifferent result will follow. For

' example, a train. traveling at a speed just above thirty miles perhour will reach the contactor 69 approximately two seconds after'enteringthe block. As previously stated, the entrance of the train intothe block immediately closes a circuit through magnet 42 to connect thesource I! to the junction point 4 I, and thispoint is connected tothetrack contactsiifi through wire 64. When the train passes over thecontactors 69, this mem her will be brought into engagement with thecontact 65, and thus current will flow through wires II and 84 to'posts8 and 82, through wire 89, and thence through the magnet I8 back to thesource through grounds l9 and I8. I

Under such eonditions; the energization of the magnet i8 is permittedfor the reason that track contactor 69 has been operated. within thetime limit necessary for the solenoid armature 98 to travel inwardlyshort of the point wherethe contacts H5 and H5 will be engaged. When themagnet i8 is thus energized it attracts its armature 87, and thecontacts 95% and 86 will be brought into engagement. Under suchconditions a holding circuit for the magnet I8. will be established fromthe junction pointwll through wire 99, base 99, bar 83, contacts 99 and36, and wire 85, and thence through themagnet I8 to ground I9. Thereleasing of the. contactor 69 after the front Wheels of the locomotivepass thereover accordand 99.

ingly will not disturb the circuit through the magnet I8 and thismagnetwill remain energized until later deenergized under conditions tobe referred to.

With the train traveling at approximately 5 thirty miles an hour, whichis the condition of operation now under consideration, it will beapparent that the armature 98 will have traveled inwardly throughapproximately half of its stroke between the time the locomotive entersthe con- 10 trol block and operates the contactor 69. When the magnet I8attracts its armature the circuit through the solenoid 99 will be brokensince the bar 89 will be disconnected fromthe stop contact 92, andaccordingly the spring I03 will start to move the armature 98 back tonormal position. It requires approximately four seconds for the armature98 to travel inwardly to its inner limit of movement, and the checkvalve I94 is so adjusted as to cause the spring I23 to return thearmature 98 to normal position at a slower rate.

In practice, it is preferred that the check valve I M be so adjusted asto permit return movement of the armature to normal position intwentysix seconds. 25

Under the conditions of operation referred to, the armature 93 will havetraveled inwardly to such a position that it will require eight secondsfor its return movement and when the normal position is reached, thegates will start downwardly in a manner to be referred to. Under suchconditions, therefore, the train will have traveled into the blockapproximately half way to the intersection and approximately ten secondshas been required for the train. to move such distance. The gatesrequire approximately ten seconds to reach horizontal position, andsince it will require another ten seconds for the train to reach theintersectiomafter the armature 98 hasreached normal position, it will be40 apparent that the gates will reach horizontal position substantiallyat the time the train reaches the intersection.

Under the conditions previously considered, the energization of themagnet I8 will have attracted its armature BI, and accordingly when thesolenoid armature 98 reaches normal position, engagement will beestablished between contacts 95 Thus current will flow from thejunction'point ll through wire 99, base 89 and bar 98, and then acrosscontacts 95 and 99, through v wires H3 and II to junction post H9. Fromthis point the current flows through wires I21 and I26, and thencethrough magnet I24 and back to the source through ground I25. Thisaction obviously energizes the magnet I24 and attracts its armature I32,thus bringing the contacts its and I 35 into engagement with therespective contacts I23 and I29 of the lever I39. This lever is pivotedto permit it to compensate 60 for any inequalities in the movement ofthe'bar I9! whereby proper electrical engagement will be establishedbetween the contacts referred to.

Upon energization of the magnet I24, current will flow from the sourceI46 through wire I41, across contacts I35 and I29, and through wire I43to the junction post we. From this point,,current flows over wire I 45which is connected to the branch wires I18 leading to the series ofsolenoids I64, and the current also flows from wire Hi5 through wire I82to the branch wires of the other series of solenoids I64.

The switch arms I19 of the two gate units will be in engagement with thecontacts I12 leading to the uppermost solenoids I64, and under thecircumstances a circuit will be completed through the uppermost solenoidI84 of each gate unit. The operation of the two gate units is identicaland only one need be referred to in detail. Upon energization of theuppermost solenoid I84 the armature I62 will start to move downwardlythus transmitting movement to the wheel I59. As

such movement is imparted to the shaft I55 and gate I 55 in a manner tobe referred to, the switch arm I13 will be moved progressively intoengage ment with the successive contacts I12 leading to the successivesolenoid coils I64. This action causes the armature I62 to be movedprogressively downwardly until the gate is closed, and when the lowerlimit of movement of the gate is reached, the switch arm I13 will engagethe last contact I12 to the right as viewed in Figure '7, thusmaintaining the lowermost solenoid I34 energized to hold the gate inhorizontal position.

Movement is not directly transmitted from the wheel I59 to the gateshaft I55, but is transmitted resiliently through the springs I 69.Referring to Figures 3 and 4, it will be seen that the lever IE5 isconnected to the wheel I59 through sleeve 58, and as the wheel I59rotates, the lever I56 moves with the wheel, thus tending to move thespring bolts I63 circumferentially out of alignment with the pin I10.This action transmits a circumferential force to the pin I13 tending torotate it to return to its normal position with relation to the boltsI68. As the wheel I59 rotates, therefore, the shaft I55 will be rotatedsimultaneously with the wheel in the absence of any disturbing force.

The switch arm I13, while shown diagrammatically in Figure '7 as beingmovable with the gate I55, is movable with the lever I66. On the otherhand, the gate I56 is not positively connected to the source of powertherefor, but derives its moving force through the springs I69.Accordingly, if movement of the gate is interfered with, no damage willresult thereto, and when the gate is released it will immediately seekits proper position with the pin I19 in alignment with the bolts Theoperation described has assumed the train to be moving toward the east,that is from the left toward the right as viewed in Figure 1, and duringthe movement of the train from the entrance into the block, to thecenter thereof adjacent the highway, the coil of the magnet 42 willremain energized in the manner previously stated. When the train passesover the insulation I5 to the right hand or east track section I4,current will flow from rail I2 through the axles and wheels of thelocomotive, through wire 62 to contacts 54 and 49, through wire 52, andthence through the coil 43 to ground 45. The previous energization ofthe magnet 42 has depressed the bar 55 and the contacts 49 and 54 willhave remained in engagement throughout the passage of the train over thewest rail section I4. The wire 62 also is connected to the contact 58,centrally of the bar 55, but engagement between the contacts 58 and 59will have been broken due to the previous movement of the bar 55downwardly.

Under the conditions stated, with part of the train on the west rail I4and part on the east rail I4, both coils 42 and 43 will be energized,and the coil 43 obviously will remain energized until the train leavesthe east end of the control block. When the rear end of the train leavesthe west block I4, the circuit from the rail I2 to the west rail I4 willbe broken, and no current will flow through the coil 42. Since thecompletion of the previously described circuit to the junction point 4|is dependent upon contact across the rails at the west end of the block,it will be apparent that the circuit to the junction point will bebroken when the train passes completely into the east end of the block.While the magnet 43' will be energized under such circumstances in themanner previously described, it will be apparent that the continuedattraction of the armature 51 retains the contact 58 out of engagementwith the contact 59, and the only circuit then completed will be thecircuit through the magnet 43 which accomplishes no other result thanthe maintenance of the bar 55 in its lower position.

The breaking of the circuit through the wire 21 when the train passescompletely into the east end of the block obviously breaks the circuitthrough the wire 39, and since the holding circuit for the magnet 18 isdependent upon passage of current through the wire 90, bar 88 andcontacts 94 and 86, the magnet 18 will be deenergized to return tonormal position, and the circuit across contacts 95 and 99 will bebroken. Of course, when the train passes completely from the east'end ofthe block, the magnet 43 will be deenergized and the springs will movethe bar upwardly to restore the normal condition of the entireapparatus.

At this point it may be stated that when the magnet I24 is energized toattract its armature, the contacts I28 and I34 will be brought intoengagement, and current will flow through wire 99, base 89, wire I2I,contact I20, wire I36 and contacts I 34 and I28, and thence throughwires I21 and I26 through the coil I24 and back to the source throughground I25. The circuit through the wire I2I thus is in parallel withthe circuit through the wire II3, but both circuits will be broken whenthe train passes from the west end of the block since such action breaksthe circuit to the junction point 4 I, and both of the parallel circuitsreferred to are dependent on the closing of the circuit through thepoint 4!. The circuit through the wire IZI is important however for areason to be described.

When the circuit through magnet I 24 is broken upon the passage of thetrain from the west end of the block, the springs I33 return the bar I3Ito normal position, thus bringing the contacts I31 and I38 intoengagement with each other. Under such conditions, current will flowfrom source I46 through wires I41 and I38, across contacts I31 and I38,and through wire I39 to the junction box contact I4I. From this point,current flows through wire I42 to the branch wires I19 of the upperseries of solenoids I55 in Figure 1, and the current also flows throughwires I84 and I83 to the branch wires I 8! of the series of solenoids Iof the other gate section. The operation of the gates of the twosections also is identical when the gates are moving upwardly, andaccordingly the operation of only one gate section need be referred to.Referring to Figure '7, it will be noted that when the gate I56 is inhorizontal position the armature I62 will be in its lowermost positionand the armature I63 in its uppermost position. At the same time, theswitch arm I13 will be in engagement with the contact I12 furthest tothe right, and accordingly the branch wires leading to the solenoids Iwill operate to complete a circuit through the uppermost solenoid,through the contact I12 referred to, through switch arm I13, and thenceback to the source through wire I48, in the case of the gate sectionshown above the rails in Figure 1. It will be noted that the switch arm"nected to the wire M8 through wire H1.

The closing .of the circuit through the uppermostxsolenoid i 65 startsthe gate section moving upwardly from horizontal position, and the H3thus moves into engagement with the successive contacts H2, and thus thearmature 41 53 will continue to move downwardly to rotate thexgatein thedirection opposite to the direction of the arrow in Figure 7 until thegate section reaches its uppermost limit of movement. It will beapparent that the armature 1:32 of magnet .124 normally is in its lowerposition, and accordingly the contacts I3! and H33 are normally inengagement. Under such conditions current liows from the battery Me inthe manner described to the branch wires of the solenoids of the twoseries I85, and when the gate is in vertical position the propersolenoids I65 will be energized to hold the gates in such position. Ifthe gates are tampered with by unauthorized persons attemptingto pullthem downwardly, such movement will be taken up by the springs Hill, andwhenever the gates are released, they will automatically return to theiruppermost positions.

As previously stated, it is preferred that means be provided forcushioning the gates as they approach their limits of movement.Referring to Figure 5, it will be noted that the shaft I55 of each gateis provided with one of the levers lot andassociated parts. Assumingthat the gate associated with the mechanism shown in Figure 5 is invertical position and starts downwardly with the shaft I55 rotating in.a clockwise dire"- tion, the lever I99 willmove freely until the pins205 reach the limits of the slotsjild, whereupon movement will betransmitted to the pistons use. The dash pots I94 containa fluid such asa light oil, and the movement of the oil past the pistons willberestricted by the openings 1%. When the point is reached wheremovement is transmitted to the pistons I95, the gates will have gatheredsubstantial momentum, but the escapement oi the oil through the openingsI95 will gradually check the movement of the gates causing them to 'betraveling slowly when they reach horizontal position. I

With thegates inlowermost position the pins 200 will be reversed inposition with respect to their slots L98, and accordingly the initialmovement of the gate back to vertical position will not be retarded.When the lost motion between the slots !98 and pins 298 is taken uphowever, theiurther ,movcment of the gates will be retarded. Inconnection with the retarding mechanism-it will be noted that the dashpots I94 are free to swing about their pivots 202 to alter theirpositions during the swinging movement of the lever l99.- i

The operation of the apparatus has-been compleiely described. inconnection with. the movement of a train traveling at a suflicient speedto depress the contactors $9 at the west end of the block before thesolenoid Q3 breaks the contact between the. posts 85 and 82. Theconditions of Operation, thus described are desirable in order that thegates may close at approximately the time'the train reaches thecrossing, such time being governed by the time element involved in the"operation of the armature 58 of the solenoid 96. 'In other Words, thelonger the train requires to pass from the entrance of the block to thecohtactor 69, the longer will be the time required for the solenoid 98to return to normal position and enter the closing of the gates. Suchoperation or" course takes place provided the train idepresses thecontactor 69 before the armature 98 has moved to its inner limit ofmovement.

A different result is obtained in the case of a very slow moving train,or one which stops within the block before approaching the highway. Aslow moving train, suc'hlas a freight-train, or one coming to astop at astation preceding the highway i 5, passes over the contactor =83 afterthe armature Q8 has moved the arm 92 to separate the contacts H5 and .2i5, and thus the operation of the contactors 69 does not lower thegates. If such train comes to a stop, or continues to proceed at aslowrate, it will pass over the contactors 'i i at a relatively shortdistance from the highway. Atsuch time it is, of course, desirable tolower the gates.

As previously described, the entrance of the train in o the blockestablishes a circuit under all conditions as far as the junction pointB]. When a slow moving train passes over the contactors i l, when thegates have not been previously lowered, current will flow to thejunction point ll in the manner previously described, thence throughwires 64 to contact 61, through the .contactor'it and wires '56 and T!to the juncticn contact H3. From this point the circuit will becompleted through magnet !24 to lower the gates in the manner previouslydescribed. The passage of one pairof wheels or one truck of the trainpast the contactors H to release-it will not affect the gates, since themomentary energization of the magnet 12 i brings the contacts E23 and!34 into engagement with each other." Under such conditions a holdingcircuit will be established for the magnet I24 from the junction point.li, through wire'iiu, base 89 and wire E2i to the junction contact i253.From such point, current flows through wire' I36, across contacts lS-tand IE8, through wires E21 and I26, and thence through magnet 124 toground I25. Thus the gates will continue to move downwardly, and theholding circuit just described will remain closed as long as the trainremains in the control block to establish a circuit to the junctionpoint @L. The passage of the train past the control block releases thecircuit to the junction point H, and thus the magnet 124 will bedeenergized to drop its armature and thus establish the circuitsnecessary for raising thegate.

The operation of the system under various conditions has been describedin detail with relation to a train moving through the control block fromthe west toward the east; The operation of the system when a train ismoving from the east toward the west is identical, the actuation of thedepressor ill causing the same result asthe actuation of the depressor69, while the actuation of the depressor l5 by a slow moving traincauses an operation identical with that following the actuation of thedepressor M. In this connection it will be noted that the contactors Mand T5 are both connected to the wire it, which in turn is connected tothe wire El, and accordingly it will be obvious that each causes thesame operation,

il i) regardless of the direction from which the train approaches, ifprevious operation has not taken place through the movement of arelatively rapidly moving train. 1

The only diiferencebetween the operation of the contactors 69 and i9lies in the fact that whereas the circuit is established by an ,eastbound train to the junction point 4| upon energization of the coil t2,the approach of a train from the east initially causes operation of themagnet 29. A train approaching from the east connects the rail I2 to theeast rail section I4, and thus current will travel from the latter overwires 62 and 63 to contact 58. Since the bar 55 is in normal positionunder such circumstances, the contact 58 is in engagement with thecontact 59, and-current thus flows from the latter contact through wire28 to coil 2I and thence back to the source through ground 23. Thisaction attracts the armature 42 of coil 2|, thus bringing the contacts36 and 38 into engagement, whereupon the circuit to the junction pointt! is established from wire 28 through wire 29, across contacts 30 and38 and through wire 49. From this point, the operation of the systemthrough magnet I8, solenoid 96, etc., is identical with the operationpreviously described. The purpose of pivoting the lever 3| is the sameas in the case of the lever is, such pivot means being provided toinsure proper contact between the contacts 30 and 38. l

The energization of coil 2i obviously also brings the contacts 26 and3'! into engagement with each other, and the passage of the west boundtrain into engagement with the west rail I4 then causes current to flowthrough wires 2'! and 39, across contacts 3'! and 2t, and thence throughwire 24 and coil 29 to the ground 22. Thus the magnet 20 will beenergized to retain its armature t2 and the bar 34 in lower position tohold the circuit across the contacts 33 and 35 open and prevent thecompletion of a circuit to the point 4i as would occur by the movementof an east bound train. Accordingly the gates will open when a westbound train completely clears the east end of the control block.

From the foregoing description it will be apparent that energization ofthe magnet I24 is dependent upon closing the circuit across the contactsH9 and I20, provided however that a circuit is established as far as thejunction point 4I. Under some conditions it is desirable to provideauxiliary means for shunting across the contacts I I 9 and I 29, andsuch means is provided in the form of the switch I49 and push buttonI5I, while an auxiliary depressor I52 may be employed. If desired, theshunt circuit may be closed through the medium of the microphone I53upon the blowing of the whistle of the locomotive. These auxiliary meansfor closing the shunt circuit are desirable for use where it isnecessary to drop the gates from different points in the block for anyreason, or where portions of a block are needed for switching cars. Theyare unnecessary however to the normal operation of the system described.

Audible and visible signals may be used in connection with the movementof the gates, and. such signals have been illustrated. In thisconnection, attention is invited to the fact that the timing mechanismfor operating the gates upon actuation of .either of the contactors 69or I9, depending upon the direction of approach of the train, causes thegate to be lowered preferably in ten seconds, and the gate preferablyreaches its lowermost or horizontal position at the instant the trainreaches the intersection. Accordingly the movement of the gate itself isa signal to approaching persons or vehicles that a train is approachingbut it is preferred that additional signals be employed as stated.

Referring to Figure 1 it will be noted that each gate unit is providedwith a light signal E88 and an audible signal I9I, preferably in theform of a bell. The switch arm I rotates with the gate shaft of eachgate unit, and is normally out of engagement with its segmental contactI86. Upon initial movement of the gate downwardly from verticalposition, the arm I85 comes into engagement with the contact I86. Undersuch conditions, current flows from the source I! through wire I93 tothe signal I9I of the upper gate unit in Figure 1, and the branch wireI92 leads to the signal IEH of the other gate unit. The signal circuitsare otherwise the same and only one need be described. For example, fromthe upper signal iSi in Figure 1 current flows through wire I99, throughthe light I88 and wire 539 to the switch arm I85, thence to the contactI36 and back to the source through ground Hill. The contact I86 ispreferably of such length that it will be engaged by the arm I85throughout the movement of the gate, and thus it will be apparent thatthe signals I88 and I9I will operate immediately after the gate startsits downward movement, and will continue to operate as long as the gateis down, and until it again returns to its normal vertical position.

From the foregoing it will be apparent that the present apparatusprovides a fully automatic system for operating railway crossing gates,and that the system automatically takes into account the speed of anapproaching train, and accordingly the gates are lowered at the propertime, and are never lowered an unnecessarily long time before the traincrosses the intersection. If the contactors 69 and I9 were operative forclosing circuits to operate the gates immediately upon the approach of atrain, the gates would have to be timed to close with respect to thefast moving train, and thus would close entirely too soon for slowmoving trains, as previously stated. Moreover, the present systemeliminates the operation of the gates in the case of a train enteringthe block and stopping before it reaches the intersection. The auxiliaryshunt circuit closing devices I49, I5I, I52 and I53 are for optional useto supplement the normal operation of the system where local or specialconditions make such operation desirable.

The system also provides safety features in the operation of the gates.For example. if a gate should be pulled down across the highway while notrain is passing, the gate action would not be disturbed, the longsprings I69 permitting the gate to be drawn down without affecting theother parts of the apparatus. The gate would promptly return to normalposition as soon as released. Moreover, if a gate should be held downthrough unauthorized tampering after a train has passed the highwayintersection, the gate action would not be injured for the same reason,and the gate would move to inoperative position upon its release. If avehicle should attempt to pass under the gates as they start down, thegate may come to rest on the top of the vehicle but would cause nodamage thereto due to the action of the springs I69. After passage ofthe train, the gate would be picked up from such intermediate positionon top of the vehicle and would return to normal position. No weightexcept the pull of the springs I69 would rest on the top of the vehiclesince the gate is counterbalanced, and no damage would result to thevehicle. In this connection attention is invited to the fact that thegates move downwardly approximately 45 fairly rapidly and are thenchecked by the dash pots, and the gates accordingly are prevented frommoving at such rate as they approach operative position as would causeinjury to persons or vehicles.

It, is to be understood that the form of my invention herewith shown anddescribed is to: be taken as a preferred example of the same and thatvarious changes in the shape, size, and arrangement of parts may beresorted to without departing from the spirit of the invention or thescope of the subjoined claims. I

I claim: 7 V

1. Apparatus of the character described comprising a gate for a railwaygrade crossing, means for operating said gate to move it betweenvertical inoperative position and horizontal operative position, saidoperating means comprising a gate lowering solenoid device and agateraising solenoid device each having a circuit therefor, a switchnormally closing the circuit through the second named solenoid deviceand movable to operative position for closing the circuit through thefirst named solenoid device, an operating magnet for said switchenergizable to move said switch to operative position, and control meansforsai d operating magnet comprising a solenoid energizable by a'trainpassing a predetermined point in advance of the grade crossing, anarmature for said solenoid having means for. retarding its movement uponenergization of the solenoid, said armature also having means tendingto-urge itto normal position upon deenergization of said solenoid toclose a circuit through said operating magnet, and a track devicearranged between the grade crossing and said predetermined point andoperative by a train passing thereover for deenergizing said solenoid.

.2. Apparatus constructed in accordance with claiml provided with meansoperative a predetermined time after initial energization of saidsolenoid for preventing energization of said operatingmagnet if morethan a predetermined time is requiredfor the train'to pass from saidpredetermined point to said track device.

3. Apparatus constructed in accordance with claim 1 wherein the circuitof said solenoid in cludes a control magnet having an armature normallyoccupying a position to close a circuit through said solenoid upon thepassage of a train past said predetermined point, the circuit of saidcontrol magnet being adapted to be closed upon actuation of said trackdevice and including a switch operative to be opened by the armature ofsaid solenoid if said control magnet is not energized by actuation ofthe track device within a predetermined time after the passage of atrain past said predetermined point.

4. Apparatus of the character described comprising a gate for a railwaygrade crossing, a pair of electromagnetic devices one of which isoperable for moving the gate downwardly to operative position and theother of which is operable for moving the gate upwardly to inoperativeposition, a circuit for each of said electro-magnetic devices includinga switch normally in a position energizing said second namedelectro-magnetic 'device, a magnet for moving said switch to anoperative position for closing a circuit through the first namedelectro-magnetic device, a solenoid energizable when a train approachesthe grade crossing and reaches a point located a predetermined distancetherefrom, an armature for said solenoid, a bellows having one endstationary and the other end connected to said solenoid, means asociatedwith said bellows for restricting the movement of air into and out ofthe bellows to retard movement of said armature, means tending to movesaid armature to a normal position outwardly of said solenoid, meansoperative when the train has traveled a predetermined distance afterenergizing said solenoid for breaking the circuit therethrough, andmeans for energizing said magnet to move said switch. to operativeposition after the armature of said solenoid has returned to normalposition. i

'5. Apparatus constructed in accordance with claim 4 provided with meansoperative for preventing the breaking of the circuit through saidsolenoid if the aproaching train requires more than a predeterminedlength of time for reaching the solenoid circuit breaking means.

6; Apparatus or the character described com distance therefrom, anarmature for said solenoid,

means for retarding the movement of said armature, resilient meanstending to urge said armature to a normal position outwardly of saidsolenoid, trackway means, located betweensaid predetermined point andthe grade crossingand operable by a train passing thereover for breakingthe circuit through said solenoid provided the train moves from saidpredetermined point to said trackway device within a predeterminedminimum time, means for preventingthe open ing of the solenoid circuitby said trackway device after saidsolenoid has been energized a pre--determined length of time, means operative by said armature when itreturns to normal position after having been energized for moving saidswitch to operative position, and'trackway means independent of saidfirst named. trackway means andlocated near'the grade crossing formoving said switch to operative position upon the passage of a trainthereover if said switch has not been previously moved to such position.

'7. Apparatus of the character described comprising, a gate for arailway grade crossing movable downwardly to horizontal operativeposition and upwardly to vertical inoperative position, a pair of seriesof superimposed axially aligned solenoids, an armature for each seriesof solenoids connected to the gate to transmit movement thereto, aswitch operative by the gate, a series of contacts engageable by theswitch, the contacts of said series starting from one end thereof beingconnected to the successive solenoids of one series starting from oneend thereof and to the solenoids of the other series starting from theother end thereof, a feed wire for each series of solenoids, a source ofcurrent, a switch normally connecting the source of current to the feedwire leading to one series of solenoids, said second named switch beingmovable to an operative position to complete a circuit including saidsource and the feed wire leading to the other series of solenoids, trainoperated means including a trackway device located in advance of thegrade crossing and operative by a train passing thereover from apredetermined point in advance thereof within a predetermined length oftime for moving said second named switch to operative position,andtrackway means for effecting movement of said second named switch tooperative position if said trackway device is not actuated within saidpredetermined length of time, said trackway means being located betweenthe grade crossing and said trackway device.

8. Apparatus of the character described comprising a railway blockextending substantially equidistantly on opposite sides of a gradecrossing and insulated from the rails extending beyond the ends thereof,a gate for the grade crossing, power means connected to the gate to moveit downwardly to a horizontal operative position and upwardly to avertical inoperative position, control means for said power meansincluding a trackway device located a predetermined distance from eachend of the block, a solenoid energizable upon the entrance of a traininto the block and including an armature, means for retarding movementof said armature, spring means tending to return said armature tooperative position outwardly of said solenoid, means operative uponactuation of said trackway device for deenergizing said solenoid, acircuit adapted to be closed upon the return of said armature to normalposition after said solenoid has been deenergized for rendering thepower means operative for lowering the gate, means for rendering eachtrackway device inoperative for opening the circuit through saidsolenoid if an approaching train requires more than a predeterminedlength of time after entering the block for reaching one of saidtrackway devices, and trackway means arranged between the grade crossingand each of said trackway devices for rendering the power meansoperative for moving the gate to operative position if said power meanshas not been previously rendered operative by the train passing over oneof said trackway devices.

9. In a gate operating mechanism for railway grade crossings, a railblock forming a part of the railway and extending from the crossing inthe direction of train approach, a gate, means for lowering said gate, acontactor arranged intermediate the ends of the rail block, a movablemember, means for limiting the speed of movement of said movable member,means urging said movable member in one direction to a normal position,means for initiating and continuing movement of said movable member inthe other direction upon and after the entrance of a train into saidblock, means operative by a train passing over said contactor forreleasing said movable member for movement toward normal position, meansfor preventing operation of said last named means if the train requiresmore than a predetermined time interval for passing from the entranceend of the block to said contactor, and means rendered operative by saidmovable member as it returns to normal position after hav ing beenreleased by operation of said contactor for actuating said gate loweringmeans.

10. In a gate operating mechanism for railway grade crossings, a railblock forming a part of the railway and extending from the crossing inthe direction of train approach, a gate, means for lowering said gate, acontactor arranged intermediate the ends of the rail block, a movablemember, means for limiting the speed of movement of said movable member,means urging said movable member in one direction to a normal position,means for initiating and. continuing movement of said movable member inthe other direction upon and after the entrance of a train into saidblock, means operative by a train passing over said cont-actor forreleasing said movable member for movement toward normal position, meansfor preventing operation of said last named means if the train requiresmore than a predetermined time interval for passing from the entranceend of the block. to said contactor, means rendered operative by saidmovable member as it returns to normal position after having beenreleased by operation of said contactor for actuating said gate loweringmeans, and a second contactor arranged between said first namedcontactor and the gradecrossing for actuating the gate lowering means ifthe latter has not been previously actuated by the passage of a trainover said first named contact-or.

ALFRED E. MCCLAREN.

